Re: [PATCH] neigh: Support filtering neighbours for L3 slave

On 8/3/21 12:47 AM, Lahav Schlesinger wrote:

quoted

quoted

quoted

you can not special case VRFs like this, and such a feature should apply
to links and addresses as well.

Understandable, I'll change it.
In this case though, how would you advice to efficiently filter
neighbours for interfaces in the default VRF in userspace (without
quering the master of every interface that is being dumped)?
I reckoned that because there's support in iproute2 for filtering based
on a specific VRF, filtering for the default VRF is a natural extension

iproute2 has support for a link database (ll_cache). You would basically
have to expand the cache to track any master device a link is associated
with and then fill the cache with a link dump first. It's expensive at
scale; the "no stats" filter helps a bit.

This is the reason for kernel side filtering on primary attributes
(coarse grain filtering at reasonable cost).

Nice, didn't know about the ll_cache.
Does filtering based on being in the default VRF is something you think
can be merged into iproute2 (say with "novrf" keyword, following the "nomaster"
convention below - e.g. "ip link show novrf")?
If so I'll add it as a patch to iproute2.

yes. There is also an outstanding request to show the vrf of neighbor
entries (e.g., add a new column at the end with vrf) when doing a full dump.